In message , Alan Silver
writes
I have a planted tank that isn't doing so well anymore. This is partly
due to my lack of time on it and partly due to the way the wind has
been blowing, the alignment of Jupiter as opposed to my lunch
yesterday, etc.
rambling snipped

I realised last night that I never actually said what the problem is !!

The plants are still growing, albeit slowly, but a lot of the leaves are
raggedy at the ends. Old leaves suffer much more quickly than they used
to. I have a small amount of light green algae that grows on the glass,
but this is not much and comes off very easily with a pad. There is some
black algae growing in small clumps at the edges of many plants leaves
and some pinkish algae (I presume it is) amongst the Java moss (which is
still growing quite well).

Water is soft, neutral and well conditioned. Last time I checked,
ammonia and nitrites were zero and nitrates were about 12.5mg/l. I do
twice-weekly 10% water changes.

Hope this helps. TIA

--
Alan Silver
PSG Fish Tanks - http://fish.alansilver.co.uk/